#1  
Old 08-08-2018, 05:18 PM
Tropo-Bob (Bob)
Registered User

Tropo-Bob is offline
 
Join Date: Sep 2013
Location: Cairns
Posts: 1,584
AQUILA - The Grand Tour

Below are the subjects in Aquila that I wish to view:-


Objects of interest.

Eta Aql. A well know Cepheid variable. Its magnitude ranges from 3.5 To 4.3 over 7 days. One day, I will buy myself a decent camera and take some wide-angle images of this.
https://en.wikipedia.org/wiki/Eta_Aquilae

Pi Aql. A close binary. (Separation 1.4", mags 6.3 &6.8)
https://en.wikipedia.org/wiki/Pi_Aquilae

15 Aql. A colourful double.
https://en.wikipedia.org/wiki/15_Aquilae

57 Aql. A showpiece double near the boarders with Capricornus & Sagittarius.
https://en.wikipedia.org/wiki/57_Aquilae

Struve 2644. Location 20h.12; + 0.52. (Separation 2.6", mags 6.9 & 7.1)


The Main Stars.

Alpha Aquilae (Aql). Altair is one of the vertices of the very large asterism known as the Summer Triangle (the other two vertices are marked by Deneb and Vega.) Altair is only 17 LYs away.
https://en.wikipedia.org/wiki/Altair

Beta Aql. Alshain is a subgiant with 1.3 Solar masses and with a luminosity 6 times the Sun. 45 LYs away.
https://en.wikipedia.org/wiki/Beta_Aquilae

Gamma Aql. Tarazed is a young star (100 million years old) that will become a white dwarf. 395 LYs away.
https://en.wikipedia.org/wiki/Gamma_Aquilae

Delta Aql. Okab. An astrometric binary some 51 LYs away.
https://en.wikipedia.org/wiki/Delta_Aquilae

Epsilon Aql. Deneb el Okab (meaning the tail of the eagle) is a giant star some 155 LYs away.


Note. I do not report on the already well-known Messier and Caldwell objects, but these are those in Aquila:
Messiers: Nil
Caldwell: Nil
Reply With Quote
  #2  
Old 11-08-2018, 09:04 AM
Tropo-Bob (Bob)
Registered User

Tropo-Bob is offline
 
Join Date: Sep 2013
Location: Cairns
Posts: 1,584
My observations

I viewed these on the evening of 8th August. Alpha to Delta Aql were visible to the eye without difficulty, Epsilon was visible with difficulty.

I used my Orion 80mm Triplet (FL 480mm, on an AZ mount.) For EPs, I mainly used a 24mm Panoptic, 5.7 & 15mm Radians, and a 3mm Long Pern.

I did return to this on the evening of 10th August to split one double that the 80mm could not resolve.


Objects of interest.

Eta Aql. A well know Cepheid variable. Its magnitude ranges from 3.5 To 4.3 over 7 days...
I found this easily, as it is in a direct line from Eta to Delta. I estimated its magnitude to be similiar to Beta Aql, which is mag 3.9.

Pi Aql. A close binary. (Separation 1.4", mags 6.3 &6.8)
I returned to this last night (10/8) with a larger telescope after failing to split this double on 8/8 with an 80mm scope, using 160x

I split this with 140x using a Meade ED 127mm (F9). I correctly estimated the Magnitude difference between the two stars as 0.5mag. I also took a stab at the PA and thought it was roughly 90 degress. Since it is 106 degrees, I was roughly right. Lol.

I actually first split them with a Vixen 8mm LVW EP. They appeared tight, but cleanly separated. Then I tried a 7mm Delite (160x), which resulted in a slight drama. The split was vague and not nearly as clean. This is when I noted the PA. Finally, I used a 6mm Radian (190x) and the split again looked clean. I love the lightness of the Delites compared to the Radians at higher magnifications, but this is the second time that I noticed a Radian EP showing better detail than a Delite of similar FL.


15 Aql. A colourful double.
Even at 20x, the split looked wide. However, this is a beautiful, colourful double, which is located almost on the boarder with Scutum.
The colours looked to be a light-orange primary, with the companion being red. The pair was about 1 mag difference in magnitude. (Note: Difference is actually 1.5).


57 Aql. A showpiece double near the boarders with Capricornus & Sagittarius.
A striking pair of bright, white stars that were separated with 20x. The stars were only slightly unequal in magnitude.

Struve 2644. Location 20h.12; + 0.52. (Separation 2.6", mags 6.9 & 7.1)
A pair of near equal stars split with 95x, though the view was better using 160x


The Main Stars.

Alpha Aquilae (Aql)... Altair is only 17 LYs away.
Appear to be a slightly creamy white.

Beta Aql.
Light orange or perhaps a deep yellow. Sometimes the longer I look, the more uncertain I become.

Gamma Aql.
Gamma is somewhat brighter than Beta. It appeared orange.

Delta Aql.
Appeared white.

Epsilon Aql.
Appeared orange.
Reply With Quote
  #3  
Old 11-08-2018, 04:33 PM
Tinderboxsky's Avatar
Tinderboxsky (Steve)
I can see clearly now ...

Tinderboxsky is offline
 
Join Date: Feb 2012
Location: Kingston TAS
Posts: 1,031
Excellent report Bob. Thanks for sharing. I have completed two of your other tours; just need to find some time to post. Too busy at the moment with non astronomy things which seems all wrong in retirement.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 12:59 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement